The cryptotephra layer also confirmed the optically stimulated luminescence (OSL) technique being developed by Zenobia Jacobs of the University of Wollongong, Australia.

This dates the last time individual grains of sand were last exposed to light.

“There has been some debate over the accuracy of OSL dating, but Jacobs’ age model dated the layers where we found the Toba shards to about 74,000 years ago — right on the money,” Marean says.

SURVIVORS

The Earth-shattering power of supervolcano eruptions has been inferred by the enormous extent of their lava flows, and the impact of the more recent — and much smaller — explosion of Mount Tambora in 1815.

This Indonesian produced what has become known as ‘The Year Without Summer” in 1816. Crops failed in Europe, Asia and North America.

Famine was unleashed across the northern hemisphere.

The Toba supervolcano eruption would have dwarfed this.

Given the size and extent of its ash fall, it seems reasonable to believe its winter lasted for several years.

“Many previous studies have tried to test the hypothesis that Toba devastated human populations,” Marean says. “But they have failed because they have been unable to present definitive evidence linking a human occupation to the exact moment of the event.”

But the Pinnacle Point excavations are clearly concurrent to the supervolcano eruption.

Every sample was carefully recorded and chemically analysed.

And the story they tell is unexpected.

“These models tell us a lot about how people lived at the site and how their activities changed through time,” says associate research scientist with the Institute of Human Origins Erich Fisher. “What we found was that during and after the time of the Toba eruption people lived at the site continuously, and there was no evidence that it impacted their daily lives.”

At the very least, this study shows the inhabitants of the food-rich African coasts thrived through this apocalyptic time.

Further study is needed to determine if similar pockets of survivors were dotted around the world. Or if those who clung to life on this rocky headland represent the ancient origin of us all.